Studies will be continued on the oxidative killing mechanisms of neutrophils. With whole cells, the effect of oxygen tension on O2 production will be examined, and O2 production by Chediak-Higashi cells will be studied. Further investigations of hydroxyl radical (OH) formation by neutrophils will be carried out, and the role of the cell wall in the resistance of bacteria to destruction by this agent will be studied. Solubilization and purification of the enzyme responsible for O2 formation in stimulated neutrophils will be attempted. BIBLIOGRAPHIC REFERENCES: Cheson, B.D., Curnutte, J.T. and Babior, B.M.: Oxidative killing mechanisms of neutrophils. Prog Clin Immunol 3: 1-65, 1977. Mauck, L. and Babior, B.M.: Inactivation of ethanolamine ammonia-lyase by 5,5'-dithiobis(2-nitrobenzoic acid). Further evidence for the involvement of sulfhydryl groups in adenosylcobalamin-dependent rearrangements. Biochem Biophys Acta 480: 489-494, 1977.